I hate to have to do it!!! Growl/harmonic vibration. Opinions Please

I've been trying to identify the cause for weeks. But no luck. Hopefully someone has had a similar experience and fixed it before it broke.

I have this growl type vibration that is felt once i get to 60 MPH...the vibration is strongest between 60 - 70...55 it's not too bad and 70 and beyond it's not too bad. I feel the vibe in the floor board and gas peddle. I let off the throttle and it goes away. It does it in O/D and third at the speeds mentioned above.

This started after i had to use the winch to get out of a mud hole...I'm thinking i worked the tranny trying to rock out before goin to the winch...Just looking for folks opinions before i start breakin into things lookin for problems that aren't there.
Anyone have a similar experience???

the only thing i haven't done is replace the front joints...it would be nice if that what it is!!! just doesn't feel like a vibe that would come from a ujoint...but i guess i should handle all the simple suspects before attacking the tougher ones!

Which front ujoints are you going to replace? The ujoints in the front drivetrain won't have any effect on vibration at highway speeds unless you're in 4WD at those speeds. /forums/images/graemlins/yikes.gif If you're talking about the front ujoint in the rear driveshaft then go for it.

bearings front and rear replaced....rear driveshaft joints replaced and yolk is tight...that's why i hated to make this post....other than a tranny or tcase issue, i can't think of any other cause...the vibration feels like it's comming from the front and not the rear...

There are many possibilities...too many with what we know. Have you tried to listen for the vibration with the vehicle sitting still and holding the engine at rpms for a couple of minutes? If it is an engine issue, it might show up here. But, most likely it is drivetrain or chasis. Bearings (double check) are a common failure that make this sort of sound. If the new ones were over-torqued they could be the culprit. It takes some time to find these problems... /forums/images/graemlins/confused.gif

I know man...it's the hunt that won't end!!! I replaced the bearings last weekend and it made no change in the vibe....I've tried holding the RPMS around 3500-4000 and no vibe...runin through the gears at higer rpms doesn't vibe either...only when i'm at highway speeds...something about rotation at 65...I haven't checked for motor flex yet...so i haven't ruled out a bad motor mount when the drive train is being torqued to make 65mph...the worst, or best, depending how u look at it, is the vibe hasn't worstened...it just showed up one day and hasn't gotten any better or worst with all the things i've done to combat it...which also makes me think it may be the motor mount...i'm gonna check all drivetrain mounts to be safe...

You've done a bunch of work but still have the noise..........have you tried blocking the front wheels and putting the rear up on solid jackstands and running the truck at the same MPH that produces the noise? If the noise shows up you could crawl around and try to find where its coming from.

i guess i could try that!!! i'd have to pull my balls out of the ole ladies purse to give that a go!!! just something about a truck spinnin at 65 in the air!!! i trust my jack stands and all!!! that kinda reminds me of the guy who went shark divin' without a cage and became din-din!!!

Have you tried to rotate your tires? If it is a bent wheel or a tire problem swaping them from the front to the back would make it feel different. You could of also lost some wheel weights and now it is out of ballance.

Edit: oh and I'd be scared to run a rig at 65 on jack stands too /forums/images/graemlins/shocked.gif

i wish that were it...i'm a former firestone employee and generally a tire or wheel will be felt in the seat for the rears or the steering wheel for the fronts...similar to diagnosing rotor/drum and pad/shoe trouble...bein' it's in the gas peddle and floor board, it has a high chance of being drivetrain...aint rulin' nothin' out though!!

Why woulden't you feel a tire vibe in the gas pedal....its connected to the firewall witch is connected to the frame witch is connected to the axle......

Vibes in a rig are never cut and dry. Just because you felt a rear tire vibe in the seat once doesn't mean you will feel a rear tire vibe only in the seat on another car.

As far as tire vibes and ware you feel it....my wheeler vibrates everything above 65, the side mirrors look fuzzy because the vibes are so bad at that speed. But 44's on a 4500lb rig are going to do that to you. Even on my daley driver, when I put on the buckshots for hunting season the t-case shifters vibrate...that doesn't nesessaraly mean that the t-case or motor mounts are bad.

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